Elevator having reciprocating plates positioned and driven by rack and pinion structure

ABSTRACT

In an elevator having a series of juxtaposed plates reciprocated alternately in opposed directions to elevate articles step by step from a receiving location to a delivery location, novel structure wherein two adjacent plates in the series have at their sides a pair of opposed gear racks, each pair being drivenly engaged with an intermediate pinion, the pinions supporting the plates against tilting toward either side thereof.

United States Patent 1 Ford [ 51 July 17,1973

[ ELEVATOR HAVING RECIPROCATING PLATES POSITIONED AND DRIVEN BY RACK AND PINION STRUCTURE [76] lnventorz' Paul A. Ford, 29753 Somerset,

Southfield, Mich. 48075 [22] Filed: Sept. 28, 1971 [21] Appl. No.: 184,407

[52] [1.8. CI. 198/219 [51] Int. Cl. 865g 25/04 [58] Field of Search 198/218, 219; 74/29,

[56] References Cited UNITED STATES PATENTS 3,139,973 7/1964 Rivers 198/218 8/1899 3/1972 Green 198/218 Primary Examiner-Edward A. Sroka AttorneyBarnes, Kisselle, Raisch & Choate [5 7] ABSTRACT In an elevator having a series of juxtaposed plates reciprocated alternately in opposed directions to elevate articles step by step from a receiving location to a delivery location, novel structure wherein two adjacent plates in the series have at their sides a pair of opposed gear racks, each pair being drivenly engaged with an intermediate pinion, the pinions supporting the plates against tilting toward either side thereof. 1

11 Claims, 7 Drawing Figures Lloyd 74/110 7 Patented July 17, 1973 4 Sheets-Sheet 2 FIG. 3

INVENTOR. PAUL A. Foao M" ATTOQNEYS Patented July 17, 1973 4 Sheets-Sheet 1;

INVENTOR. G- v PAUL A. Foao BY M, KM 76%? M ATTORNEYS Patented July 17, 1973 4 Sheets-Sheet 4 FIG. 7

INVENTOR. PAUL A. FbRD A TTORNEYS ELEVATOR HAVING RECIPROCATING PLATES POSITIONED AND DRIVEN BY RACK AND PINION STRUCTURE This invention relates generally to an elevator of the type which utilizes a series of juxtaposed plates arrayed between a receiving location and an elevated delivery location, the plates being reciprocable in alternately opposite directions for elevating articles step by step from the receiving location to the delivery location. An elevator of this type is disclosed in my U.S. Pat. No. 3,547,253. More particularly, the invention relates to structure by which the plates are supported in their proper orientation and by which the plates are reciprocated.

As is shown in the above mentioned patent, it is conventional to support and reciprocate certain ones of the plates in the series by means of chains entrained around sprockets, one or more of which is driven. The chains have runs which are attached to the sides of the plates and means are provided for adjusting the lengths of the runs to adjust the tilt of the plates relative to their sides. Elevators having this structure have been very successful commercially. However, the chains must be adjusted occasionally to correct undesirable tilt of the plates, particularly where relatively heavy loads are being elevated.

The object of the present invention is to provide a relatively simple drive structure for the plates which is improved to support the plates rigidly in their proper orientation without the necessity for adjustment and which is, nevertheless, more economical to manufacture.

In general, the invention is carried out by mounting a pair of pinion gears on the frame of the elevator and providing a gear rack on each side of two adjacent plates in the series, the two racks at each side being opposed and being in dental engagement with opposite portions of the pinion gear at that side. The gears rigidly support the plates against tilting toward either side. When the gears are driven alternately in opposite directions, the two plates are reciprocated in opposite directions. Other plates in the series are reciprocated and supported against tilting by bars attached to the sides thereof and to the sides of one of the first two plates. One form of the invention is shown in the accompanying drawings.

FIG. 1 is a partly diagrammatic perspective view of a housing and elevator according to the present invention.

FIG. 2 is an enlarged generally sectional view on line 22 of FIG. I with parts broken away to illustrate structural details.

FIG. 3 is a view generally similar to FIG. 2 but taken on a more central vertical section and illustrating a dif- Icrent position of the parts.

FIG. 4 is an enlarged sectional view on line 4-4 of FIG. .2. 2

FIG. 5 is an enlarged sectional view on line 55 of FIG. 3.

FIG. 6 is an elevational view taken in the direction opposite from that of FIGS. 2 and 3, parts being broken away to illustrate structural detail.

FIG. 7 is a generally elevational view of a modified elevator according to the present invention, parts being broken away and shown in section to illustrate structural detail.

Shown in FIG. 1 is an elevator according to the present invention mounted in a housing 22, the housing being provided with a chute 24 through which articles are fed to the elevator. Elevator 20 has a frame comprised of two sides 26 and 28 and a back 30. A series of elevator plates 32, 34, and 36 are mounted for reciprocation within the frame in a linear direction which slopes upwardly from the bottom end 38 of chute 24 to a discharge shelf 40 on back 30 adjacent the top of the elevator. Plates 32-36 have tops 42 44, and 46 respectively forming shelves upon which parts are elevated.

Frame sides 26, 28 are provided with three slots 48, S0, and 52 which extend parallel to the direction of movement of plates 32-36. Each plate 32-36 has side portions 54 at its opposite sides disposed adjacent the inner surfaces of frame members 26, 28. A lug 56 is anchored on each side portion of each of plates 32 and 34. Lugs 56 project through slots 48 and 50 and each lug is anchored to a gear rack 58. A pair of gear racks is thus disposed adjacent the outer side of each frame member 26, 28 and the racks of each pair are in opposed relation. Each gear rack is slidably abutted against a supporting rail 60, the rails being anchored on frame sides 26, 28.

A lug 62 on each side 54 of plate 36 projects through adjacent slot 52 and is connected to the upper end portion 64 of a bar 66 whose lower end portion 68 is secured to the gear rack 58 and lug 56 on plate 32. A spacer 70 is provided between bar 66 and lower rack A drive shaft 72 is rotatably mounted on frame members 26, 28 with its axis extending substantially horizontally, A pinion gear 74 is affixed adjacent each outer end portion 76of the shaft and each gear has opposite peripheral portions dentally engaged with a pair of gear racks 58. Shaft 72 has a drive sprocket 78 mounted adjacent one end 76 thereof.

A chain 80 is entrained around sprocket 78 and a sprocket 82 on the output shaft 84 of a power unit comprised of an electric motor 86 and reduction gearbox '88. Motor 86 is connected into electric circuitry which includes lower and upper limit switches 90 and 92 (FIG. 6) whose trip levers 94 and 96 respectively are mounted in the path of movement of a trip cam 98 secured on a gear rack 58.

When motor 86 is actuated to drive sprocket 78 in one direction the sprocket in turn rotates shaft 72 which drives pinion gears 74. The two pinion gears drive the gear racks 58 passinG above them in one direction and the gear racks passing below them in the opposite direction thereby moving plates 32 and 34 in opposite directions. When the direction of motor 86 is reversed, pinion gears 74 reverse the direction of movement of plates 32 and 34. Bars 66 drivingly interconnect plates 32 and 36 so that these two plates move together in the same direction. Lugs 56 and 62 by sliding engagement within slots 48, 50, and 54 respectively serve to guide movements of the plates. Rails 60 serve as guides and load bearing members for gear racks 58.

An important feature of the invention is that plates 32-36 are rigidly' supported against tilting toward frame sides 26, 28 by gears 74 which are in turn firmly mounted on framemembers 26, 28'tht0ugh shaft 72.

Gear racks 58 cooperate in maintaining this positive against lateral tilting since they are connected to the sides of plate 32 which is firmly secured against tilting as described.

The drive is very simple in that it comprises merely a single drive shaft 72 and pinion gears 74 thereon. Should it be desired to move plates 32, 34 through different strokes, differential drive gearing could be provided between pinions 74 and selected gear racks 58. Since the gears and gear racks are disposed at the sides of plates 32-36, they remain free of dirt and other foreign matter which might sift or fall from the plates.

In operation, let it be assumed that a quantity of articles has been placed in chute 24 and that motor 86 is operating in such a direction as to move plates 32-36 from the solid line position of FIG. 3 toward the dotted line position. When shelf 42 on plate 32 lowers into alignment with lower portion 38 of chute 24 articles slide from the chute onto shelf 42. At the same time, trip cam 98 engages toggle lever 94 to operate limit switch 90 for reversing the direction of motor 86. Thereupon plate 32 elevates and plate 44 descends.

When the solid line position of FIG. 3 is attained, shelves 42 and 44 are aligned so that the articles transfer onto shelf 44. Trip cam 98 engages toggle 96 to operate limit switch 92 for again reversing motor 86. The plates then return to their dotted line position wherein the articles slide from shelf 44 onto shelf 46 and motor 86 is again reversed. In the next cycle of operation, shelf 46 is elevated to'alignment with discharge shelf 40 and the articles slide over this shelf and discharge onto a conveyer C or other receiver. The cycle continues with shelf 42 receiving a new supply of articles on each downward stroke thereof, the articles being elevated step-by-step to shelves 44 and 46 and being discharged on each upward strokeof shelf 46.

The elevator illustrated in FIG. 7 is similar to that described above except that the frame is extended upwardly and a fourth elevator plate 100 is added to the series. This plate is driven and supported against lateral tilting by a pair of arms 102 anchored to the sides of plate 34 and to the sides of plate 100. Plate 100 has a top 104 forming a shelf which receives articles from shelf 46 on plate 36. Operation of this form of elevator is similar to that described above except that in the final elevating cycle shelf 104 carries the parts upwardly for discharge over shelf 40.

I claim:

1. In an elevator having a series of juxtaposed plates arrayed between a receiving location and an elevated delivery location and being reciprocable in alternately opposite directions relative to each other for elevating articles step by step toward said delivery location, improved drive and support structure for said plates which comprises,

a frame having two sides-between which said plates are reciprocable,

shafting supported by said sides and upon which gearing is mounted adjacent said sides,

a gear rack mounted on each side of each of two adjacent plates in said series,

the gear racks on like sides of said plates being spaced apart and facing each other,

said gear racks extending substantially parallel to the direction of movement of said adjacent plates, said gearing including adjacent each of side of said frame a gear having portions in dental engagement with two gear racks on like sides of said adjacent plates, reversible motor means operable to drive said gears in opposite directions for reciprocating said plates,

said gears being so positioned relative to said direc tion of movement that they cooperate to maintain said adjacent plates substantially untilted toward either side thereof.

2. The structure defined in claim 1 wherein said shafting includes a single substantially horizontal shaft upon which said gears are coaxially mounted, said shaft so positioning said gears.

3. The structure defined in claim 1 wherein a pair of bars are secured to the sides of one of said plates and to the sides of a third plate, said gears, plate, and bars being cooperable to maintain said third plate substan tially untilted toward either side thereof.

4. The structure defined in claim 3 wherein said third plate is adjacent the other of said two adjacent plates.

5. The structure defined in claim 3 wherein another pair of bars are secured to the sides of the other of said two adjacent plates and to the sides of a fourth plate in said series whereby to reciprocate said fourth plate, said gears, other plate, and other bars being cooperable to maintain said fourth plate substantially untilted toward either side thereof.

6. Thestructure defined in claim 3 wherein said sides of said frame are provided with guide means which constrain said gear racks to substantially linear movement and which support said gear racks in dental engagement with said gears, said guide means including for each gear rack a rail upon which said rack is slidable.

7. The structure defined in claim 6 wherein said direction of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such side.

8. The structure defined in claim 1 wherein said sides of said frame are provided with guide means which constrain said gear racks to substantially linear movement and which support said gear racks in dental engagernent with said gears.

9. The structure defined in claim 8 wherein said guide means for each gear rack includes a rail upon which said rack is slidable.

[0. The structure defined in claim 9 wherein said di' rection of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such side.

11. The structure defined in claim 1 wherein said direction of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such 

1. In an elevator having a series of juxtaposed plates arrayed between a receiving location and an elevated delivery location and being reciprocable in alternately opposite directions relative to each other for elevating articles step by step toward said delivery location, improved drive and support structure for said plates which comprises, a frame having two sides between which said plates are reciprocable, shafting supported by said sides and upon which gearing is mounted adjacent said sides, a gear rack mounted on each side of each of two adjacent plates in said series, the gear racks on like sides of said plates being spaced apart and facing each other, said gear racks extending substantially parallel to the direction of movement of said adjacent plates, said gearing including adjacent each of side of said frame a gear having portions in dental engagement with two gear racks on like sides of said adjacent plates, reversible motor means operable to drive said gears in opposite directions for reciprocating said plates, said gears being so positioned relative to said direction of movement that they cooperate to maintain said adjacent plates substantially untilted toward either side thereof.
 2. The structure defined in claim 1 wherein said shafting includes a single substantially horizontal shaft upon which said gears are coaxially mounted, said shaft so positioning said gears.
 3. The structure defined in claim 1 wherein a pair of bars are secured to the sides of one of said plates and to the sides of a third plate, said gears, plate, and bars being cooperable to maintain said third plate substantially untilted toward either side thereof.
 4. The structure defined in claim 3 wherein said third plate is adjacent the other of said two adjacent plates.
 5. The structure defined in claim 3 wherein another pair of bars are secured to the sides of the other of said two adjacent plates and to the sides of a fourth plate in said series whereby to reciprocate said fourth plate, said gears, other plAte, and other bars being cooperable to maintain said fourth plate substantially untilted toward either side thereof.
 6. The structure defined in claim 3 wherein said sides of said frame are provided with guide means which constrain said gear racks to substantially linear movement and which support said gear racks in dental engagement with said gears, said guide means including for each gear rack a rail upon which said rack is slidable.
 7. The structure defined in claim 6 wherein said direction of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such side.
 8. The structure defined in claim 1 wherein said sides of said frame are provided with guide means which constrain said gear racks to substantially linear movement and which support said gear racks in dental engagement with said gears.
 9. The structure defined in claim 8 wherein said guide means for each gear rack includes a rail upon which said rack is slidable.
 10. The structure defined in claim 9 wherein said direction of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such side.
 11. The structure defined in claim 1 wherein said direction of movement lies on a slope, said gear racks and their respective guide rails at each of said frame sides passing, one above and the other below the gear at such side. 